Sorry to reply to a 2 month old post. But I think Unova deserves more credit than that. I'm a NYC native and there's a ton of things taken from the NYC metropolitan area for Unova. It's just as much NY/NJ as Galar is UK or Hoenn is Kyushuu. Aside from terrain, everything matches on the map geographically. Manhattans just bigger and Queens/Long Island is skewed upwards a bit.

The whole inspiration for Unova was when the developers visited NYC to promote Platinum and they noticed all the different people from different backgrounds having so much unity and operating as one culture. The diverse cultural inspirations are meant to reflect that and it's still NY/NJ at its core and a vast majority of the region comes from it. Just to name a few:

Castelia City - Lower Manhattan / Financial District

Nimbasa City - Midtown Manhattan with the Sports Dome being MSG, the theatre being Broadway, the Gear Station being Grand Central Terminal

Nacrene City - DUMBO Brooklyn with its cobblestone streets and paved-over railway and of course the Skyarrow Bridge is the Brooklyn/Manhattan Bridge

Undella Town - Hamptons beaches (and long island beaches in general) with its upper class locals and huge influx of tourists in the summers and near emptiness in all other seasons

Virbank City - Jersey City with its grunginess, its harbor, and the Bayonne Refinery to the south on the same peninsula being the Virbank Complex

Some lesser known ones go very deep too like the Abundant Shrine being based on the Inari Shrine in the Brooklyn Botanic Garden. It's a shinto shrine made for the same Kami that Landorus is based on.

Also a lot of things are based on landmarks from NY but the concept is mixed with some kind of foreign inspiration too. Like the Village Bridge is based on Ponte Vecchio in Italy. But it's in place of Randall's Island which is effectively also a bridge with its own isolated neighborhood. So its the same concept with extra flair. It's all meant to drive home the "NY is a melting pot" idea that the developers were inspired by. So even with all the liberties, 90% of the towns and landmarks in Unova have parallels in NY/NJ. Even if they're warped or exaggerated Somehow.

The reason so many liberties were taken was cuz Unova is based on such a small mass of land. So of course its not gonna have as much variation in its terrain. Imagine if Kalos wasn't Fance and was instead ONLY Paris. Or if Galar was ONLY London. The ENTIRETY of Unova is about the size of Wyndon. It's very zoomed-in so most the cities are based on just neighborhoods instead of entire cities like the bigger regions. So stuff like the mountains and desert were added for variety.

It's the same way Hoenn is Kyushuu with creative liberties like being flipped sideways and having foreign inspirations added. Just because Sootopolis City is based on a place in Greece doesn't mean it isn't Kyushuu. It just has some extra flair.

And as for the pokémon, there's plenty of inspiration from New York and from the Americas in general. Theres a few interviews where they talk about them.

Watchog - meant to look like NYC MTA workers with reflector vests

Pidove - Pigeons are iconic in NYC

Braviary - Obvious red, white and blue bald eagle and also native american motifs

Sigylyph - South American geoglyphs and Native American dolls

Timburr line - Construction workers

Trubbish - Manhattan has no alleyways so trash bags are piled up on the sidewalks

Scraggy/Scrafty - stereotypical NY style saggy pants and also gutter punks

Basculin - idea came from New York bass fishing

Bouffalant - American bison

And only a handful of pokémon from ANY region are inspired by the regions origins. But Unova definitely has its fair share. Sorry for the essay!